Conditions
allow you to change the behaviour of BPMN processes during execution. There are two ways you
are able to add decision logic to Conditions. The Camunda Modeler refers to them as Type. You can find them in the Condition tab of
certain BPMN elements. The first one is Script. This allows you to add arbitrary complexity
to your decisions logic and is rarely used for process plugins. The more common Type is Expression.
Expressions have the following syntax: ${expression}. For this tutorial, expression will
use a boolean condition like var == true. You can learn more advanced features of Expressions here.
For this to work during BPMN process execution, the variable you want to use for the boolean
condition must be available in the BPMN process variables before Sequence Flow
reaches the evaluation of the expression.